Evolving beyond point-to-point key generation toward multi-party entanglement networks linking quantum processors across a metropolis.
Multi-photon quantum interference requires spatial and temporal wavepacket overlap within picoseconds. Metropolitan nodes distribute optical frequency combs over dedicated pilot wavelengths, synchronizing single-photon detector gates down to 800 femtoseconds across 60 km city loops.
With synchronized Bell state analyzers deployed at central telecom hubs, data centers perform quantum state teleportation between remote superconducting QPUs, executing distributed CNOT gates across metropolitan distances without quantum decoherence collapse.